Strut rods

[dodj]

Adjustable strut rods available from pst and hotchkis and others have a hiem joint at the k member mounting point. The sales pitch says this allows for free'er movement of the front suspension. I'm sure it does. But is that a good thing for the way our front ends were designed? Was resistance to up and down movement by the strut rods part of the overall design?
I see the firm feel design is similar to original but is adjustable like tie rod ends. No heim joint (or similar) at the k member. They see no need to 'free' up the suspension?

Opinions anybody?
 I'm in the process of installing new torsion bars and thought I would remove the strut rods and clean them up, but if replacing them will give me better handling car, I will go with that.

[brads70]

I found when I made mine that there is a "sweet spot" when adjusting them. This would be where there is the least bind in the LCA bushing. Now with all stock parts one you can't adjust this, second with rubber bushings up front and the resistance they give you would never feel this "sweet spot" 
When I did my front end alignment in the driveway with a caster/camber gauge and toe plates/tape measure I went to a buddys garage to double check. It was very close he didn't have to adjust much, but he did like the adjustable feature in the strut rod to bring it all together for a 4 wheel alignment. Other wise it would have taken much longer shimming the rear spring hangers etc.... but then again I was being picky and wanted to hit the numbers I wanted.
I found the rod end gave me much more suspension travel, but then again how much do you need. I'd say the adjustable feature is more important then the rod end feature. But not having both makes it had to feel the sweet spot?

[dodj]

I hear what you are saying about the 'sweet spot', and it makes sense to me, factory tolerances being what they are.
The joint in the rod seems to me to add a weak spot into a rod that takes a lot of 'push - pull' abuse.
Probably thinking too hard....

[dodj]

These:
http://www.qa1.net/suspension/street-performance-racing-suspension-components/dynamic-strut-bars/mopar-dynamic-strut-bars

or these:
http://www.firmfeel.com/adjstrut.htm

or just clean up the originals and re-install.
 
 

[brads70]

When I made mine I did so because no one offered one mounted in rubber. I was concerned about road vibration/noise?  I was concerned with the qa1 design loosening  along with the solid mounting?    I'd say in your case I'd go with the firm feel set up?  The adjustment feature is a plus. You could make the stock set up adjustable by machining the shaft where it butts up against the LCA or add spacers but that's a lot of screwing around?

I found these and wondered if the black parts are solid washers or rubber?
http://www.p-s-t.com/s.nl/it.A/id.7548/.f?sc=12

[HP2]

The joint in the rod seems to me to add a weak spot into a rod that takes a lot of 'push - pull' abuse.
Probably thinking too hard....

Probably over thinking that one. The tensile strength of that threaded rod is probably substantial. I don't know how big it is, but as an example, the 9/16 tie rod ends would take 5g worth of force to shear them. Strut rods are bigger than tie rods, so it will take even more force to break them.

I've thought about welding a ring for an upper ball joint into that position on the k-frame, then using a ball joint in the front position with a threaded rod linking to the control arm.

[brads70]

Probably over thinking that one. The tensile strength of that threaded rod is probably substantial. I don't know how big it is, but as an example, the 9/16 tie rod ends would take 5g worth of force to shear them. Strut rods are bigger than tie rods, so it will take even more force to break them.

 

"I've thought about welding a ring for an upper ball joint into that position on the k-frame, then using a ball joint in the front position with a threaded rod linking to the control arm."

That's what I'm planning when I build my own k-frame. Common practice back in the day with Nascar mopars.  I have a bunch of Howe take apart ball joints to play with. Thinking I'll turn one down and thread it like and use it like a turn buckle for adjustment.
Tony if you do that I found using a tailpipe expander in the welding ring helps a ton to keep it's shape so it doesn't deform during welding.

[dodj]

Hey, thanks for the link Brad. I didn't find those when surfing pst's site.

[HP2]

Tony if you do that I found using a tailpipe expander in the welding ring helps a ton to keep it's shape so it doesn't deform during welding.

Thanks for the tip Brad, that is an excellent idea.

I might have to locate another K to start this on. My primary focus is getting my heap back on the street now, so I'm reluctant to continue with mods at risk of leaving it on jack stands for longer than I intend.

Plan is to extend the control arm lengths to create new scrub radius positions combined with different spindle heights for roll center changes and upper control arm configurations for different camber gains.

[brads70]

Thanks for the tip Brad, that is an excellent idea.

I might have to locate another K to start this on. My primary focus is getting my heap back on the street now, so I'm reluctant to continue with mods at risk of leaving it on jack stands for longer than I intend.

Plan is to extend the control arm lengths to create new scrub radius positions combined with different spindle heights for roll center changes and upper control arm configurations for different camber gains.

The later B-Body LCA's will work for length. I have them and considered using them but the problem with them is getting the ball joint up high enough towards the spindle pin to get the roll centers/instant centers down from outer space. That and I just spent a pile on new rims and didn't want to buy new rims to change the offset.  Those Laughlin spindle/steering arms will work though , keep your eyes out for a symmetrical pair.